I own a 1985 380se, a w126 model. I've read on other forums that severe vibrations at highway speeds seems to prevelant with this model set. I recenetly have had my wheels balanced, but the problem has intensified. I'm wondering if anyone has expierence with the problem and can lend their advice. Thanks!

Here's how I would figure out where the problem is:

1) Move the front tires to the rear and see if the vibration changes. If the vibration problem improves, swap each rear tire out for the spare and see if you can improve the situation further. This will help you identify a bad tire or out of balance tire.

2) Have them balanced again by an MB shop.

3) Have an MB shop do an inspection of your suspension and do an alignment if everything checks out ok.

would it matter if its not a mercedes-benz shop?

A high percentage of vibration complaints are indeed due to tire/wheel problems, the most common being imbalance.

The first thing you need to check is to see that the wheels were balanced with weights both inboard AND outboard on the wheels. It is all too common for the kids at the tire stores to use weights ONLY on the inboard rim because they have been chewed out by customers for scratching their fancy wheels.

If you have MB wheels, use the MB clip on weights and they will not scratch the wheels if properly applied.

Using inboard weights only will guarantee imbalance that will result in vibration. If you don't want weights on the outer rim, a savvy wheel balancer can use tape weights for the outer plane by putting them just behind the spokes. Most of the newer balancer machines even have functions to aid in this approach.

If your wheels are indeed balanced with weights on both planes, the next step is to seek out a Hunter GSP 9700 wheel balance machine. This balancer not only balances, but also has a pressure wheel and analyzes the tire for stiff spots. All MB dealers have these machines, but they are also found in many other shops.

To find the 9700 near you simply go to: www.gsp9700.com and there is a locator on that site.

Good luck,

I only mentioned using an MB shop because you are more likely to get the results you are after than you would using a fast lube or super tire center.

Make sure the rims are not out of round or bent.

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Fun, fun, fun

I had the same problem on my 380 I had the wheels balanced last week, and the vibration is a lot less, when driving past 60 mph. The car however does need an alignment so that might be a contributing factor. I have one ball joint with a worn out boot, but a fellow forum member doubts that to be the problem. Here is what he told me, so I'll have mine checked out soon.

"I doubt its your ball joints but if the boots are gone they definitely
should be replaced. Most vibrations are from tires irregularities or
balance but your car does have a common condition that occurs when the
rear strut mount (we call it the caster joint) becomes weak. It allows
the wheel to move forward and backward. At road speed this can cause a
vibration as the movement hits a resonant frequency."

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**A few Hondas etc... etc... Not Worth Mentioning**
83 Euro W126 380 sel Money Pit (Sold)
91 W124 300e 2.6. (Sold) 3.0 Motor is Much better!!
93 BMW E34 Touring Wagon (Sold) Sweet Car!!
91 300e (Just 200k with Ease.)Best car ever ???(Sold)
90 420sel (Black with Tan Interior) Best car ever!!!!!!!

My 126 used to vibrate so bad I thought I was going to lose control at highway speeds. I wound up rebuilding the whole front suspension, definite grunt work but fairly straight-forward and rewarding.

If your vibration is severe, Check the condition of the rubber ball joint boots including the upper control arm and the tie rods. Check for excessive play. Check the rubber bushings for cracks or deterioration. These parts wear out and need to be replaced after a long while. Also, the steering dampener is cheap and easy to install and could be a starting point if your wheels and alignment are within their proper parameters.

Good luck

Mine does that from 90mph to 100mph. No other time. Anyone have an explanation?

Thanks,

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http://comp.uark.edu/~dmgill/signature.jpg

Mine does the same thing and when i took it to a dealership to get the wheels balanced they balanced them and it still vibrated. So i asked them and they said that i needed new caster buckets. However when i put my stock rims on the problem dissappeared. So i dont know if its something with my new rims ( 7 spoke from 2000 S Class) or if its something else.
-Bob

My vibration suddenly started 2-days ago. I thought that my PS rear wheel had thrown a weight, so I had it rebalanced. But the problem is still noticeable when I hit 45mpg... and the whole car shake and sounds like I'm in the inside of a drum at 60+.

The other night, I heard a clunk as I was on my way to the airport. But as I was driving in a driving rainstorm, it was difficult to make out where the noise came from. But I don't recall sensing any vibration in the car before this event. And I am positive I did not have the problem several days earlier, as I drove home from the airport on the freeway.

I've done a cursory visual inspection and cannot see any visible signs of any defects. I also had the entire front suspension rebuilt about 18months ago, and I personally replaced many of the rear suspension components approximately 30 months ago.

Any thoughts.

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Steven
1989 260E (276K miles)
1995 E320 (50K miles)

I used to have some low speed (20~30mph) vibration that would gently shake the entire car. It was caused by one of the front tires having a lateral cut across it. The cut was very shallow and not obviously visible unless one is intently looking for it. I replaced all four tires as they had very little tread left in them any way. The new tires I chose were TOYO Proxes 205/65VR-15 purchased, balanced and installed at Les Schwab. The low speed rocking was completely eliminated but in its place I had steering wheel vibration at 60mph and above. Les Schwab rebalanced all four wheels but that didn’t solve the problem. I took the car to them again but this time I had a heart to heart discussion with the manager. They found out that one of the new tires was out of round. They replaced it and now I can drive it all the way to 100mph and it’s silky smooth. Moral of the story: Check the tires because it seems that the W126's are very sensitive to even seemingly minor tire/balance irregularities.

Cheers

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Riadh
'89 560SL Rauchsilber
And what is good, Phaedrus, and what is not good -- Need we ask anyone to tell us these things?

Jammer:
When you write that I'm assuming that you mean your 300SEL? I try not to drive my 300 SEL any faster than 75 or 80. Any speed beyond that and the engine sounds like it's spinning its brains out and it's going to send expensive parts shooting through the hood. I'm curious how many rpm's is your engine turing at 100mph?

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I'm sick of .sig files

Noticed slight vibration after tire rotation and balancing at MB dealership. Got a refund from the dealership and found a shop with the hunter 9700 machine, did not fix the vibration, it got worse.

Took it to another shop (they sell their own tires as well) with the Hunter 9700 machine, one tire had to be rotated on the wheel (slip). Road Force feature of the machine pointed out the imbalance.

Vibration gone. A shop may have the Hunter 9700, but they may not be using all the features of the machine or know how to use it properly.

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Zafar
94 E320 58000 Miles

An EXTREMELY high percentage of vibration complaints turn out to be wheel/tire problems, probably over 90%.

It's important to understand that vibration will only be CAUSED by rotating mass. Loose or worn suspension parts will not CAUSE vibration, but will AMPLIFY the vibration.

Whenever you have worn suspension parts, you should certainly see to it, but don't expect that alone to eliminate vibration. If it decreases the vibration, you are only covering up the true source of vibration, not correcting it.

It is not uncommon at all to balance, rebalance...... tires until you're blue in the face only to find that you have a tire with a broken belt or other malady. The 9700 can determine this.

Good luck,